Honda Civic 2017 Owner's Manual page 540

Vietnamese models
Unleaded premium petrol/gasohol up to E10 (90% petrol and
10% ethanol), research octane number 95 or higher
Use of lower octane petrol can cause occasional metallic knocking noise in the
engine and will result in decreased engine performance.
We recommend that you use a research octane of 98 or higher to maximize the
performance of the engine.
Use of petrol with a research octane less than 91 can lead to engine damage.
Thai models
Unleaded premium petrol/gasohol up to E10 (90% petrol and
10% ethanol), research octane number 95 or higher
Use of a lower octane petrol can cause occasional metallic knocking noise in the
engine and will result in decreased engine performance.
Use of a petrol with a research octane less than 91 can lead to engine damage.
The use of regular unleaded petrol can cause metallic knocking noises in the engine
and will result in decreased engine performance. The long-term use of regular-grade
petrol can lead to engine damage.
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Fuel tank capacity: 46.9 L
uuRefuelinguFuel Information
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